Stream : TMemoryStream;

begin

    Stream := TMemoryStream.Create;

    try

      IdHTTP1.Request.UserAgent := 'Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.3) Gecko/20100401';

      IdHTTP1.Get(TIdURI.URLEncode('http://translate.google.com/translate_tts?tl=ko&q=' + txtHangul.Text), Stream);

    finally

      MediaPlayer1.Close;

      Stream.SaveToFile(ExtractFilePath(Application.ExeName) + 'temp.mp3');

      MediaPlayer1.FileName := ExtractFilePath(Application.ExeName) + 'temp.mp3';

      MediaPlayer1.Open;

      MediaPlayer1.Play;

   end;

end;